DLV Two/Four Channel (Module 5*)
75DS2 Operations Manual
North Atlantic Industries, Inc.
11/11/2011
Rev: 2011-11-11-1000
www.naii.com
Page 22 of 43
Wrap (LVDT) Velocity
DLV Channel Signal Voltage
Each individual channel input signal voltage “V
L-L
” is measured and the value reported to a corresponding read
register. The input voltage is reported to a resolution of 10 mv rms. The output is in integer decimal format.
For
example
, if channel 1 input signal voltage is 11.8 V
RMS
, the output measurement word from the corresponding
register would be 1180.
DLV Channel Excitation Voltage
Each individual channel input Excitation voltage “VEXC” is measured and the value reported to a corresponding
read register. The input voltage is reported to a resolution of 10 mv rms. The output is in integer decimal format.
For example
, if channel 1 input signal voltage is 11.8 V
RMS
, the output measurement word from the
corresponding register would be 1180.
Signal Loss Threshold
Each individual channel input signal voltage “V
L-L
” is measured and the value reported to a corresponding read
register. The signal loss detection circuitry can be tailored to report a signal loss (at SIG Status register Ch.1-4) at
a user defined threshold. This threshold can be set to a resolution of 10 mv rms. Program the threshold by writing
the value of the voltage threshold in integer decimal format.
For example
, if channel 1 input signal loss voltage
threshold is to be 7 V
RMS
, the programmed word to the corresponding register would be 700 (2BCh).
Excitation Loss Threshold
Each individual channel input excitation voltage “VEXC” is measured and the value reported to a corresponding
read register. The excitation loss detection circuitry can be tailored to report a excitation loss (at EXC Status Ch.1-
4) at a user defined threshold. This threshold can be set to a resolution of 10 mv rms. Program the threshold by
writing the value of the voltage threshold in integer decimal format.
For example
, if channel 1 input excitation loss
voltage threshold is to be 20 V
RMS
, the programmed word to the corresponding register would be 2000 (7D0h).
DLV Write Position
Enter the position as a 2’s complement number in the corresponding Position Ch. Data Register within the range
of -1.00 < Position < (+1.00
– lsb). In 3/4-wire mode, position is written only to the A channel of that number pair;
the B channel register is ignored. In 2-wire mode the A and B channels are set independently. Factory default:
POSITION = 0
Calculate using: register value = POSITION * 32768
Example:
For a POSITION = -0.5 -> register value = -0.5 * 32768 = -16384 (0xC000)
Example:
For a POSITION = 0.75 -> register value = 0.75 * 32768 = 24576 (0x6000)
The Output voltages in 3/4-wire mode are related to the position by:
Va = Excitation Voltage * TR * [ Position/2 + 0.5 ]
Vb = Excitation Voltage * TR * [ 1
– ( Position/2 + 0.5 ) ]
The Output voltage in 2-wire mode is related to the position by:
V = Excitation Input * TR * Position
Note:
Writing to an Input Position Register will stop any rotation initiated on that channel
DLV Response / Filter Time
(Pending)
